In a conventional aerosol container (see Patent Document 1 and so on, for example), a flexible inner bag is disposed integrally in an interior of an outer can, content to be discharged is stored in an inner bag, and a pressurized fluid is charged between the inner bag and an outer can. By pressing the flexible inner bag, the content housed in the inner bag is discharged to the outside through an inflow port.
In this type of aerosol container, the content does not come into contact with the pressurized fluid, and therefore any desired pressurized fluid can be used. Further, the pressurized fluid is not discharged together with the content, and therefore the content can be discharged efficiently.
When, in this type of aerosol container, a remaining amount of the content discharged from the flexible inner bag decreases, the inner bag becomes wrinkled or bent such that enclosed spaces are formed, and the content inevitably remains in these spaces to the last.
To reduce this final remaining amount, a dip tube is conventionally attached as a remainder reducing member so that the content can be discharged to the outside from both the vicinity of the inflow port and a tip end of the dip tube.
FIG. 8 shows a conventional aerosol container provided with a dip tube.
In this example, an inner bag 502 housing content F is provided in the interior of an outer can 501 of an aerosol container 500, and the inner bag 502 is provided with a spout 504 having a stem 505 in an upper portion thereof and an inflow port 503 opened in an interior thereof.
A pressurized fluid G such as nitrogen gas is charged into a space between the outer can 501 and the inner bag 502 such that when the stem 505 is pressed, the content housed in the inner bag 502 flows into the inflow port 503 so as to be discharged to the outside from a tip end of the stem 505.
Further, a dip tube 511 serving as a remainder reducing member is inserted into the inflow port 503, and at this time, an inner periphery of the inflow port 503 is formed such that a flow passage for the content F is secured between the inflow port 503 and the dip tube 511. Hence, as shown by arrows, the content F is guided in the direction of the stem 505 from both the vicinity of the inflow port 503 and the vicinity of a tip end of the dip tube 511, and then discharged to the outside.
In another conventional aerosol container shown in FIG. 9B, a plurality of flexible inner bags are disposed in a single outer can such that different types of content can be housed without intermixing and discharged simultaneously.
With this type of aerosol container, intermixing of the content prior to discharge can be prevented completely without the need to connect a plurality of outer cans or provide special internal structures. Further, the pressurized fluid need only be charged once into the single outer can, and therefore manufacture is easy (see Patent Document 2 and so on, for example).
Patent Document 1: Japanese Patent Application Publication No. 2004-75099 (all pages, all drawings)
Patent Document 2: Japanese Patent Application Publication No. 2005-231644 (all pages, all drawings)
Patent Document 3: Japanese Patent Application Publication No. H11-105893 (all pages, all drawings)
The content that inevitably remains in conventional aerosol containers such as those described in Patent Documents 1 and 2 can be reduced to a certain extent by providing the dip tube serving as the conventional remainder reducing member described above, and in so doing, the final remaining amount can be reduced. However, when an enclosed space forms in an intermediate position removed from both the vicinity of the inflow port and the tip end of the dip tube, the content still inevitably remains in the formed space. Moreover, content also remains in the interior of the dip tube.
Meanwhile, another conventional remainder reducing member for extracting content from a flexible container, albeit not an inner bag of an aerosol container, such that no content remains is constituted by a rigid rod-shaped body having a plurality of hollowed-out portions, which is disposed to extend from an inflow port into the interior of the container (see Patent Document 3 and so on, for example).
However, a conventional remainder reducing member such as that described in Patent Document 3 is constructed on the assumption that the flexible container is pressed from the outside by a human hand to guide the content toward the inflow port.
Hence, in an inner bag of an aerosol container, the entirety of which is pressed evenly by a pressurized fluid, content remaining in enclosed spaces cannot be guided to the inflow port by these remainder reducing members, and in fact, the enclosed spaces may be increased by projecting portions and hollowed-out portions provided on these conventional remainder reducing members, leading to an increase in the remaining amount.
Moreover, increasing a pressure of the pressurized fluid simply leads to an increase in a closing force exerted on the enclosed space, and does not therefore contribute to a reduction in the remaining amount of content.